Fishing tool apparatus



Dec. 20, 1960 F. L. LE BUS, sR., ETAL 2,965,177

FISHING TOOL APPARATUS Filed Aug. 12, 1957 3 Sheets-Sheet 1 H 50 I I INVENTOR.

f, Fig/ FL. [e505 5% BY C907 1441/? ,6? ATTORA/{V M Dec. 20, 1960 F. L. LE BUS, sR., ETAL 2,965,177

FISHING TOOL APPARATUS 3 Sheets-Sheet 2 Filed Aug. 12, 1957 ww h M m. C

ATTORNEY Dec. 20, 1960 F. L. LE BUS, sR., EI'AL 2,965,177

FISHING TOOL APPARATUS Filed Aug. 12, 1957 3 Sheets-Sheet 3 I 79 my 14 INVENTOR. 59 5 Fl. 165L655 E /Z BY CEC/ Vlvre ATTORNEY Q 4 United States Patent FISIWG TOOL APPARATUS Franklin L. Le Bus, Sn, and Cecil Ware, Lougview, Tex.,

assignors to Wash Overshot and Spear Engineers, Incorporated, Longview, Tex., a corporation of Texas Filed Aug. 12, 1957, Ser. No. 677,660 10 Claims. (Cl. 166-240) This invention relates to improvements in drill collar retrieving apparatus, and more particularly, but not by way of limitation, to an apparatus for recovery of pipe or drill collars which have become stuck in an off bottom position in an oil well bore. The application is an improvement over the prior pending application of Cecil Ware, Serial No. 594,780.

In the drilling of wells by the rotary drilling method, and particularly deep oil wel s, the well bore frequently deviates from the true vertical. Such deviations are ordinarily caused by the drill bit contacting slanting geological structures and being forced from its true vertical course. When drilling a deep oil well by the rotary method, the drill bit is secured to the lower end of one or more drill collars and the drill collars are in turn suspended from a long string of dril pipe. The drill collars are tubular members, usually approximately thirty feet in length, and are substantially heavier and more rigid than the regular drill pipe. In the event the drill bit is forced from a true vertical direction during the driling operation, the drill collars will contact the side of the well bore and tend to remain in a vertical pos tion. When this occurs, continued rotation of the drilling string will cause the drill collars to rub the side of the well bore and form a smaller bore in the earth slightly off-set from the well bore formed by the drill bit. These off-set bores formed by the drill collars are commonly known as key seats.

When a drill bit is being removed from a well bore containing one of these key seats, the bit frequently becomes lodged therein to prevent immediate removal of the complete drilling string from the well bore. The usual practice, when such a condition occurs, is to disjoint the drill pipe and a portion of the drill collars for removal from the well bore, while leaving the drill bit and one or more drill collars lodged in the key seat. In some instances, the drill pipe or collars may become broken off and stuck oif the bottom of the bore. Under either condition, it is customary for retrieving the lodged pipe to wash over and around the stuck portion of the pipe by the use of a wash-over pipe carrying a spear apparatus engageable with the upper end of the stuck pipe so that upon a loosening of the stuck pipe, the spear apparatus will be engaged with the wash-over pipe and prevent the loosened pipe from falling to the bottom and subsequently pulled out of the well bore. Furthermore, the wash-over pipe may be removed with the spear apparatus and the connecting stuck fish without performing a stripping operation during removal.

This invention is generally concerned with a retrieving spear apparatus having a plurality of slips adapted to engage a wash-over pipe having a reamer attached, thereby providing a fishing string which is lowered into the well bore until contact is made with the stuck fish at which time the spear apparatus is threadedly engaged with the stuck fish through the combined lowering and rotation of the fishing string. After engagement of the spear apparatus, the spear slips are placed in 21 released position relative to the wash-over pipe to permit a continued downward movement of the wash-over pipe and reamer for clearing the well bore throughout the stuck portion of the fish. The spear apparatus includes hydraulic packer units capable of controlling the retractable slips of the spear unit so as to maintain the slips in a reeased position and prevent any outward movement of the slips during an upward movement of the washover pipe, thereby providing for a vertical upward movement of the wash-over pipe without any engagement of the slips. Upon loosening of the fish in the well bore, the spear unit connected therewith is so constructed to cause a substantially immediate outward movementof the slips and re-engagement thereof with the wash-over pipe to catch the loosened fish and prevent any further downward movement thereof in the well bore. 7

It is an important object of the present invention to provide a spear unit adapted to cooperate with a washover pipe for retrieving stuck pipe wherein the spear unit may be alternately engaged or released with the washover pipe so that engagement will permit movement of the spear unit with the wash-over pipe, or in disengagement will permit movement of the wash-over .pipe relative to the spear unit, thus providing vertical movement of the wash-over pipe if desired ,after connection of the spear unit with the stuck pipe, but leaving the spear unit in a position to engage the wash-over pipe in the event the stuck fish should become loosened and drop in the well bore.

A further object of this invention is to provide a well tool having a spear apparatus adapted to be supported in a wash-over p'pe for rotation with the wash-over pipe in the well bore, and capable of engagement with a fish lodged in the bore, yet permitting continued downward movement and rotation of the wash-over pipe after engagement of the spear apparatus with the lodged fish.

Another object of this invention is to provide an improved retrieving tool for recovery of lodged drillcollars in a well bore by catching the drill collars when they become dislodged from the bore.

Still another object of this invention is to provide a Well tool adapted to be alternately anchored and released relative to a wash-over pipe disposed in a well bore, and utilizing an application of hydraulic pressure in a manner to maintain the tool in a released position relative to the wash-over pipe.

And still another object of this invention is to provide a wash-over tool apparatus for retrieving stuck drill collars in a well bore having a spear unit engaging the stuck fish in the well bore wherein said spear unit is normally anchored to the wash over pipe for rotation therewith, yet may be releasably disconnected therefrom so that independent vertical movement of the wash-over pipe relative to the spear unit may be obtained and thereby-providing variable movements or complete removal of the wash-over pipe leaving the spear unit engaged with the fish.

And still another object of this invention is to provide a fishing tool apparatus for retrieving drill collars stuck ofi bottom of a well bore including a spear unit alternately anchored and released relative to a wash-over pipe and reamer and engageable with the stuck collars in a released position to permit continued reaming of the wash-over pipe and reamer and provided with hydraulic actuated packer means normally maintaining the spear unit in a released position with the wash-over pipe, but upon loosening of the stuck collars are responsive to an increased fluid pressure to assist in actuating the spear unit into immediate engagement with the wash-over pipe and prevent any further downward movement of the loosened collars.

Other objects and advantages of the iny ention will the eyident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate our invention.

In the drawings:

j Figures 1A and 1B are fragmentary side elevational views with certain parts in cross section illustrating a preferred embodiment of the invention and depicting the well retrieving tool independent of the wash-over pipe, Fig. 1B is a downwardly extension of Fig. 1A.

Figure 2 is a view taken on lines 22 of Fig. 1A.

Figure 3 is a view taken on lines 3-3 of Fig. 1B.

Figure 4 is an elevational view partly in section showing the tool anchored in a wash over pipe.

Figure 5 is a view similar to Fig. 4 showing the position of the tool in a released position relative to the wash-over pipe for relocation therein.

Figure 6 is a view taken on lines 6-6 of Fig. 5.

Figure 7 is a view taken on lines 77 of Fig. 4.

Figure 8 is a view taken on lines 8-8 of Fig. 4.

Figure 9 is a view taken on lines 9-9 of Fig. 4.

Figure 10 is a view taken on lines 10-10 of Fig. 5.

Figure 11 is a view taken on lines 1111 of Fig. 5.

Figure 12 is a view similar to Fig. 4 showing the tool in released position during a wash-over operation.

Figure 13 is a similar view showing the retrieving tool entering into connection with the fish member.

Figure 14 is a similar view showing the fish dislodged and causing actuation of the anchoring mechanism of the tool.

Figure 15 is a view in elevation showing a special wrench for use with the tool.

Figure 16 is a sectional view taken on lines 16-16 of Fig. 1B and showing the locking key arrangement.

Referring to the drawings in detail, particularly Figs. 1A and 1B, reference character 2 designates generally a well retrieving tool comprising an upper coupling 3 having an upper threaded box 4, and a lower box 5 threadedly connected to an elongated mandrel 6. The mandrel 6 is provided with left hand threads 7 upon which is threadedly secured a cylindrical wedge member 8 having inclined or inwardly tapered outer face 9 for a purpose as will be hereinafter set forth. The upper portion of the wedge 8 is provided with an aperture 10 disposed at right angles to the vertical axis of the mandrel 6 and adapted to receive a pin 11 (Figs. 1A, 9 and 10) held in place by any suitable keeper ring 12 disposed in a counter-sunk groove 13 (Fig. 2) provided conterminous with the outer end of the aperture 10. At the upper end of the left hand threads 7 on the mandrel 6 is provided an outwardly extending boss 14 adapted to cooperate with an upwardly extending boss 15 provided on the upper face of the wedge 8 in order to limit the upward movement of the wedge 8 as will be hereinafter set forth. The mandrel 6 is provided with an aperture 16 disposed substantially adjacent the top of the threads 7 and is adapted to receive the pin 11 at a predetermined position as will be hereinafter explained. An outwardly extending boss member 17 is provided on the outer periphery of the wedge 8 conterminous with the top edge thereof for a purpose as will be hereinafter set forth.

A sleeve member 18 is slidably disposed on the mandrel 6 below the bushing 3 and extends downwardly around the mandrel 6 into connection with a lower sleeve 19 as will be hereinafter set forth. The upper sleeve 18 is of a reduced diameter providing a shoulder 20 for receiving an auxiliary sleeve 21 having inwardly tapered faces 22 in which isadapted to be disposed a circular fluid restriction member 23 of any suitable flexible material, such as rubber or the like, but not limited thereto. The restriction member 23 has a lower tapered face 24 complemena tary to the taper 22 of the sleeve 21 to facilitate disposition therein. The restriction member 23 is provided with a straight vertical bore portion 25 engaging against the outer periphery of the sleeve 18. The member 23 is provided. with an upwardly elongated irregularly shaped leg memher 26 disposed in spaced relation to the outer periphery of the sleeve 18 for a purpose as will be hereinafter set forth. A spacer sleeve member 27 is disposed in a recessed portion 28 of the flexible restriction member 23 adjacent the outer periphery of the slidable sleeve 18 and held therein by a nut 29threadedly secured at 30 to the upper end of the sleeve 18, thereby maintaining the fluid restriction member in position relative to the upper end of the sleeve 18.

The outer periphery of the sleeve 18 is provided with a plurality of circumfereutially spaced recesses or windows 31 (Figs. 1A and 8), each adapted to receive a friction block 32. The friction blocks 32 are provided with upper and lower tapered flange portions 33 cooperating with keeper screws 34 threadedly engaged at 35 with the sleeve 18 for maintaining the friction blocks 32 thereon. Each of the friction blocks 32 are provided with vertically spaced pockets 36 each having one end of a helical spring 37 anchored therein with the opposite end 38 anchored at the outer periphery of the sleeve 18. It will be apparent that the compression of the springs 37 will maintain the friction blocks in a radial outward disposition against their keeper screws for a purpose as will be hereinafter set forth.

The inner diameter of the sleeve 18 is enlarged at 39 providing an outwardly disposed downward extension 40 substantially covering the threaded portion 7 of the sleeve and the wedge portion 8. The wedge portion 3 is adapted to move vertically or telescopically in the outer sleeve portion 40 in a manner as will be hereinafter set forth. The downwardly extending sleeve portion 40 is provided with a plurality of circumferentially spaced windows or recesses 42 in which are disposed a plurality of circumferentially spaced slips 43 having serrated teeth 44. The inner face of the slips 43 are tapered at 45 complementary to the inwardly tapered face of the Wedge 8, and are normally held in an inward disposition by the helical springs 46 anchored in a recess portion .-7 of a downwardly extending flange 48 provided at the lower portion of the slips 43, and the inner periphery 4% of the sleeve portion 40. The sleeve portion at its lower end has a groove 50 providing a key way adapted to receive a pin 51 for connection with the lower sleeve member 19 as will now be explained.

The lower slidable sleeve member 19 is disposed on the outer periphery of the mandrel 6 immediately below the enlarged sleeve portion 40, and the sleeve 19 has an outwardly extending flange 52 upon which rests the lower end of the sleeve portion 40. In similar manner, the sleeve 19 is provided with a groove 53 in alignment and complementary to the groove 50 for reception of the key or keeper ring 51 interconnecting the upper and lower sleeve members. It will be apparent that the upper portion 54 of the sleeve 19 telescopes slightly into the lower portion 40 of the upper sleeve. The lower sleeve 19 is of a reduced diameter at 55 for receiving an auxiliary ring 56 similar to the upper ring 21, but disposed in an opposite or inverted direction thereto. A lower flexible flow restriction member 57 is disposed adjacent sleeve 19 in a manner similar to the upper restriction member 23, but in inverted relation thereto. The lower end of the sleeve 19 is threaded at 58 for threadedly receiving a keeper nut 59 cooperating with a spacer sleeve 60 for maintaining the flow restriction member on the sleeve 19. The fluid packer member 57 is provided with a plurality of circumferentially spaced apertures 57a for a purpose as will be hereinafter set forth.

The sleeve 19 is provided with a plurality of circumferentially spaced recesses or windows 61 in which are disposed the lower friction blocks 62 similar to the upper friction blocks 32, and connected with the sleeve 19 by the keeper screws 63 in a similar manner. Likewise, a plurality of helical springs 64 are anchored in pockets 65 for urging the friction blocks 62 radially outward for a purpose as will be hereinafter set forth.

A lower bushing member 66 is threadedly connected to the lower end of the mandrel 6 (Fig. 16), and the bushing is provided with a plurality of circumferentially spaced apertures 67 providing fluid circulation outlets for the fluid circulation in a manner as will be hereinafter set forth. The lower end of the bushing 66 is provided with a threaded pin member 68 for a field connection with the threaded box of a lodged or stuck drill collar or fish in a well bore as will be hereinafter set forth. The inner periphery of the threaded box 68 is provided with a plurality of diametrically opposed key ways 69 for cooperation with the dogs or key members 70 of a cylindrical wrench member 71 shown in Fig. 15 as will be hereinafter set forth.

The outer periphery of the lower sleeve 19 is provided with an aperture 72 (Fig. 1B) in which is disposed a key 73 extending through the sleeve 19 and into disposition in a J-shaped recessed portion 74 provided in the mandrel 6 for a purpose as will be hereinafter set forth.

Operation In operation, the retriever tool 2 is preferably disposed in the lower end of a wash-over pipe 75 at the surface of the well prior to lowering in the well bore. The disposition of the tool 2 is just above the reamer shoe 76 of the wash-over pipe 75. Upon disposition of the tool unit 2 in the wash-over pipe 75, the wrench member 71 and key 70 engage the keys 69 in the lower end of the bushing 66 for rotating the bushing and mandrel 6 secured thereto in a counter-clockwise direction for tightening the unit 2 in the wash-over pipe. Any unthreading of the bushing 66 by movement of the mandrel and bushing in a counter-clockwise direction with the tool 71 is prevented by the key member 90 (Fig. 16) disposed in :aligned recesses 91 and 92 of the bushing 66 and mandrel 6, respectively. The key is held in place by a suitable :stud 94. It will be apparent that the key 90 acts as a locking stud and prevents unthreading of the bushing member 66. However, the key may be removed by re- =lease of the stud 94 to permit the unthreading of the bushing 66 when desired. The upper and lower friction :shoes 32 and 62 are engaged with the inner periphery of ithe wash-over pipe, consequently the sleeves 18 and 19 are held substantially firm to preclude vertical or rotative movement thereof.

Consequently, rotation of the bushing 66 in a counter-clockwise direction will provide simultaneous rotation of the elongated mandrel 6 in a direction that will cause movement of the wedge 8 downward on the left hand threads 7, thereby moving the serrated slips 43 radially outward into a more positive engagement with the inner wall of the wash-over pipe 75. Any further rotation of the mandrel 6 will attempt a movement of the wedge 8 downwardly on the threads 7, but the wedge cannot move vertically downward because of the engagement of the cooperating'slips 43 with the inner Wall of the wash-over pipe 75. However, a continued rotative torque on the mandrel 6 will secure the slips 43 in engagement with the wash-over pipe to the degree of torque applied to the wrench 71, and it will thus be seen that the retrieving tool 2 may be anchored in the wash-over pipe 75 in a substantially positive securement prior to insertion in the well bore.

In the anchoring of the retriever tool 2 in the wash-over pipe 75, the pin 11 will be disposed out of the aperture 16 (Fig. 2) provided in the mandrel 6, thereby leaving the wedge 8 free to move vertically, as well as rotate with re ard to the mandrel 6. The released position of the pin 11 from the mandrel 6 allows the mandrel threads 7 to revolve freely in the threads'7a of the wedge 8 for movement as is desired. Furthermore, the key or dog member 17 (Figs. 1A and 9) is slidably secured in t e key way 78. thus preventing any rotation of the wedge 8 relative to the sleeve 18.

After the retrieving tool unit-2 is securely anchored'in the wash-over pipe 75, the wrench member 71 may be removed and the wash-over pipe run into the well bore in the conventional manner. It will be understood that the wash-over string is supported at the surface of the well by suitable slips in the rotary table (not shown) in the usual manner. The wash-over string, including the wash-over pipe 75 and the tool unit 2 disposed therein, is lowered in the well bore 79 until the threads 68 of the bushing 66 enter the top of the lodged drill collar or fish 80 (Fig. 13) for making up or connection therewith by a continued rotation of the wash-over pipe 75 in a clockwise direction. As the fish is contacted, a slight tension or pull upward is made on the wash-over pipe 75 and the slips 43. A rotation of the wash-over pipe in a clockwise direction is then continued, and since the slips 43 are more firmly anchored to the wash-over pipe, the sleeve 18 will rotate around the mandrel 6, thereby causing the wedge 8 engaged with the slips to travel vertically upward on the left hand threads 7 of the mandrel 6 until the upper boss member 15 on the wedge 8 engages the boss member 14 on the mandrel 6, thereby precluding upward travel of the wedge -8. In this position, the pin 11 is brought into alignment with the aperture 16 in the mandrel 6. A spring member 81 disposed in an aligned aperture 10 of the wedge 8 forces the 'key 11 into the aperture 16, thereby interlocking the wedge 8 and the mandrel 6. In this tensioned condition, a continued rotation of the wash-over string will securely tighten the retrieving tool 2 and the bushing 66 into the box portion of the fish 80.

As soon as the retrieving unit 2 is securely made up or connected with the lodged fish 80, it is necessary to release the slips 43 from engagement with the inner periphery of the wash-over pipe 75 so that upon continued rotation and downward vertical movement, the wash-over pipe 75 and the reamer shoe 76 will move downwardly past the point of the make up connection for reaming out the well bore around the fish 80 stuck off bottom of the bore to cause an eventual loosening thereof. By slacking off or letting down on the washover pipe 75 from the surface of the well bore, it will be apparent that the slips 43 will be moved downwardly away from the inwardly tapered face 9 of the wedge 8 thereby releasing them from disengagement with the inner wall of the wash-over pipe 75. In this manner, the wash-over string is in the position shown in Fig. 12 and ready for the wash-over operation below the make up connection, and the only elements engaging with the wash-over pipe are the friction shoes 32 and 62. However, it will be apparent that 'the downward rotative movement of the heavier Wash-over pipe 75 will overcome the friction of the engaging shoes 32 and 62 to permit the continued Wash-over operation.

In the wash-over operation, drilling fluid from the surface of the well is circulated through the tool unit. However, the flow of the circulating fluid is restricted by the flexible fluid packer member 23, thereby forcing the circulating fluid to discharge through the tubular mandrel 6 and out the circulating apertures 67 around the reamer shoe 76 and up through the annulus 85 between the wash-over pipe 75 and the well bore 79. It will be apparent that with the slips 43 in disengaged or released position from the wash-over pipe during the wash-over operation, any upward movement of the wash-over pipe 75 would tend to move the slidable sleeves 18 and 19 upwardly due to the friction contact of the friction shoes 32 and 62, thereby having a tendency to engage the slips 43 with the wash-over pipe. In many instances, it is desired to'move the wash-over pipe relative to the retrieving tool 2 after the tools connection with the lost fish without a re-engagement of the slips 43, such as when it is desired to'add a new section of pipe to permit the continued wash-over operation downwardin the well bore.

In order'to preclude the re-engagement of the slips 43, the tendency of .the upward movement of the slidable hold the retrieving unit 2 and the sleeves 7 sleeves 18 and 19 is overcome by the hydraulic fluid pressure acting on the tool and particularly on the fluid packers 23 and 57. In this operation in order to provide the necessary hydraulic pressure, the pump pressure at the surface of the well for the circulating fluid is increased, thereby increasing the differential fluid pressure between that in the chamber 86 of the tool and that in the annulus 85 between the wash-over pipe 75 and the well bore 79, causing an increased fluid volume for maintaining engagement of the packers 23 and 57 with the wash-over pipe 75 and preclude any movement of the slip cage or sleeve 40. However, it has been found that when the reamer 76 is drilling in hard formations, such as chert or the like, in what is commonly known as hard reaming, the bore hole will fit tight around the reamer or milling shoe, in what is known as a tight hole condition, and an increase of fluid pressure setting the packers 23 and 57 sometimes provides a back pressure on the lower packer 57 which is greater than the fluid pressure against the top fluid packer 23. In such instances, this back pressure in acting against the lower packer 57 may cause the slip cage 40 to move upwardly and set the slips 43, thereby precluding any upward movement of the wash-over pipe 75 when desired. In order to overcome an increase in back pressure, the lower packer 57 is provided with the apertures 57a for relieving such back pressure and causing a static condition for the fluid pressure throughout the tool. The back pressure condition is caused by the fluid building up against the lower packer 57 faster than it can discharge through the circulating hole 67. However, the build up of back pressure does have a particular advantage upon the loosening of the fish 80 in a manner as will be hereinafter set forth, since when the loosened fish and the retrieving tool 2 start to move downwardly the fluid pressure is increased against the bottom packer 57 to assist in the engagement of the slips immediately with the wash-over pipe 75. This hydraulic pressure application permits vertical movement upward of the Wash-over pipe 75 without a re-engagement of the slips 43 with the wall thereof and without putting the tool in a positive released position by utilization of the pin 73 and the J-slots 74 such as shown in Fig. 5. The utilization of the J-slots necessitates a considerable yo-yo action or reciprocal vertical movement of the wash-over pipe 75 in order to locate the slots 74, and the application of hydraulic pressure eliminates this for a more efficient operation. The hydraulic pressure in the chamber 86 above the upper restriction member 23 (Fig. 12) will 18 and 19 and the slips 43 in a released position permitting any desired vertical movement of the wash-over pipe 75 without a re-engagement of the slips 43. In this manner, any number of pipe sections may be added without re-engaging the slips, and the wash-over operation may be continued with a combined downward and rotative movement of the wash-over pipe 75 and the reamer tool 76 until the fish 80 becomes dislodged or unstuck and starts to fall vertically downward out of the wash-over pipe 75 to the bottom of the well bore 79. In many instances, the stuck fish may have been stuck several hundred feet off the bottom of the well bore, and such a drop of the dislodged drill collars would have several detrimental effects. Upon the dislodgement of the fish, the mandrel 6 and the wedge 8 will move downward simultaneously therewith and in conjunction with the back pressure of fluid against the lower packer 57 will cause the slips 43 to be forced radially outwardinto an immediate gripping contact with the inner wall of the wash-over pipe 75, thereby preventing falling of the fish 80 any substantial distance toward the bottom'of the well bore. The slidable sleeves 18 and 19 are held in frictional contact with the inner wall of the wash-over pipe 75 by the friction shoes 32 and 62, and consequently will tend to remain stationary during the downward movement of the mandrel 6 and the wedge 8 in order that the slips 43 may be moved radially outward. It will be apparent that substantially instantaneous with the start of the downward movement of the dislodged fish, the cooperating tapered surfaces of the wedge 8 and the slips 43 will start radial outward movement of the slips 43 for substantially contemporary engagement of the slips 43 with the inner wall of the wash-over pipe 75.

The wash-over pipe and the retrieving tool unit 2 engaging the dislodged fish may now be removed from the well bore in the usual manner. The wash-over operation after the make up connection of the retrieving unit 2 with the lost fish may have extended through several hundred feet downward, thereby changing the original position of the retriever unit 2 in the wash-over pipe 75. Consequently, when the section of wash-over pipe 75 in which the retriever unit 2 is disposed reaches the surface of the well, it is preferable to relocate the retriever unit 2 in a lower section in the wash-over pipe to prevent an expensive stripping operation of the unit 2. The wash-over pipe 75 is secured at the surface of the well in rotary table slips and in order to relocate the fishing tool unit 2 in the wash-over pipe, it is necessary to make up a string of letting in string 87 (Fig. 5) with the upper end of the bushing 4, thereby providing a connection with the fishing tool unit 2. After the make up connection is made, the letting in string 87 may be lifted up to move the mandrel 6 upward and the wedge 8 away from the slips 43, thereby disengaging the slips from the inner periphery of the wash-over pipe 75. The lifting up of the mandrel 6 with a simultaneous righthand rotation in the string 87 will rotate the key 73 into the J-shaped recess 74 as shown in Figs. 5 and 6, thereby providing a positive released condition for the slips 43 relative to the wash-over pipe 75. With the retrieving tool 2 in this position, it may be lowered into any desired lower section of the wash-over pipe 75. In order to reset the tool unit 2 in a lower section, it is only necessary to lift or pick up on the letting in string 87 with a simultaneous counter-clockwise rotation thereby releasing the pin 73 followed by a subsequent letting in of the string 87 to move the wedge 8 and its tapered face 9 into cooperation with the slips 43 for movement of the slips in a radial outwardly direction for re-engagement with the wash-over pipe 75. The upper bushing or sub 3 may be provided with a locking key arrangement similar to that for the lower bushing 66 as shown in Fig. 16 to preclude any disengagement thereof. In this manner, the retrieving tool is reset in the wash-over pipe after which the letting in string 87 may be disengaged from the tool unit and removed from the well bore with a subsequent continued removal of the wash-over pipe by sections from the well bore.

When the last section of wash-over pipe 75 is ready to be removed from the well bore, the connecting fish 80 will be extended from the end of the wash-over pipe and may be set in rotary slips (not shown) at the well surface in the conventional manner. After engagement of the fish at the well surface, a left hand counterclockwise rotation on the wash-over pipe 75 will position the key 73 in the J-slot 74, thereby releasing the tool unit 2 and permitting the wash-over pipe 75 and shoe 76 to be removed from the well bore, leaving the fishing tool unit 2 threaded or made up into the top end of the fish 80 all secured in the rotary table at the sun face of the well (not shown). The tool unit may then be removed from the fish 80 with a subsequent removal of the fish from the bore without an expensive stripping operation of the complete tool unit The J-slot 74 and the rotatable key 73 are convenient for use in the above stripping operation, and similar arrangements have long been used in fishing tool apparatus to maintain slips in a position of release permitting vertical movement of a retrieving tool for various purposes. However, at several thousand feet in a well bore during a vertical reciprocation of the outer or wash-over pipe, the J-slots are diflicult to locate, and considerable trial and error is usually necessary in order to properly engage a key in a J-slot. The use of the present hydraulic fluid packers through the increase of the pump pressure precluding engagement of the slips on vertical movement of the wash-over pipe is immediate and increases the efiiciency of this operation greatly.

From the foregoing, it will be apparent that the present invention is useful and efiicient for the recovery of drill pipe, drill collars and the like, which have been stuck in a well bore off the bottom thereof, and where the stuck portion may be broken off or uncoupled at a joint with the stuck portion disposed in the well bore therebelow. The present apparatus provides for a washing over around the stuck portion of the pipe with a washover pipe and reamer having a retrieving tool disposed in the lower end thereof and engaging the upper end of the stuck pipe so that when it is washed free and becomes loosened, the pipe is prevented from falling to the bottom of the well by engaging the retrieving tool to the wash-over pipe after which it may be removed from the well bore, along with the wash-over pipe. Furthermore, the present invention is constructed and operated in a manner which is rugged in construction and simple in operation and particularly wherein one set of slips operates both anchoring slips for securing the retrieving tool in the wash-over pipe, as well as catching slips for engagement with the wash-over pipe upon a loosening of the stuck fish, thereby catching the loosened fish and preventing any dropping thereof to the bottom of the well bore. The apparatus contemplates a release of the slips for a continued downward movement of the wash-over pipe and its reaming shoe, yet permits vertical upward movement of the wash-over pipe with the slips retained in a released position through the application of hydraulic pressure utilized with flexible packer members on both sides of the slips to assure retention of the slips in a released condition, thereby permitting manipulation of the wash-over pipe to add additional sections of drill pipe without any hinderance from the slips. The invention contemplates for an initial anchoring of the slips in the wash-over pipe by rotation of the tool after disposition in the wash-over pipe.

Changes may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

We claim:

1. In a Wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the washover pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said cooperating means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, and means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position in response to upward movement of the wash-over pipe, means cooperating between the sleeve and the slips for moving the slips radially inward and out of engagement with the washover pipe in the last mentioned position for the wedge, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

2. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the Washover pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said cooperating means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the sleeve and the slips for moving the slips radially inward in the last mentioned position for the wedge, flange means provided on the mandrel and the Wedge for limiting the movement of the wedge in the last mentioned direction, and means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

3. in a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the washover pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, means cooperating between the mandrel and the Wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, a bushing connected to the lower end of the mandrel for a make up connection with the stuck fish, means on the bushing adapted to receive a wrench to provide rotation thereof simultaneous with the mandrel prior to disposition of the retrieving tool in the well bore to cause vertical movement of the wedge in the direction to cause engagement of the slips.

with the wash-over pipe, said cooperating means between the mandrel and the wedge responsive to an upward pull,

of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first. mentioned rotation to move the wedge in a direction;

11 opposite to that of the first mentioned direction, and means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last men- 'tioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, means cooperating be- '-'tween the sleeve and the slips for moving the slips radially inward and out of engagement with the wash-over pipe ;in the last mentioned position of the wedge, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened :fish.

4. In a wash-over apparatus for retrieving a stuck fish 'in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slid- :ably disposed on the mandrel, friction dog means carried ':by the sleeve for frictionally engaging the wash-over pipe, :a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, left hand thread means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to pro- -vide for radial outward movement of the slips for en- :gagement with the wash-over pipe, means connected to the mandrel for a make up connection With the stuck fish, said left hand thread means between the mandrel and the wedge responsive to an upward pull of the washover pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, and means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, means cooperating between the sleeve and the slips for moving the slips radially inward for a disengagement with the wash-over pipe in the last mentioned position of the wedge, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

5. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the washover pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said cooperating means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the mandrel and the wedge to provide an interlocking thereoetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response todownward movement of the wash-over pipe, means cooperating between the sleeve and the slips for moving the slips radially inward out of engagement with the wash-over pipe in the last mentioned position of the wedge, means providing for fluid circulation through the retrieving tool, and flexible packer means carried by the slidable sleeve and responsive to an increased hydraulic pressure of the fluid circulation to maintain the sleeve in a position to preclude engagement of the slips upon any vertical upward movement of the wash-over pipe, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

6. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictionally engaging the wash-over pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said cooperating means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, means cooperating between the sleeve and the slips to move the slips radially inward out of engagement with the washover pipe in the last mentioned position of the wedge, means providing for fluid circulation through the retrieving tool, and spaced flexible packer means carried by the slidable sleeve, the uppermost of said packer means responsive to an increased hydraulic pressure of the fluid circulation to maintain the sleeve in a position to preelude engagement of the slips upon any vertical upward movement of the wash-over pipe, the lowermost of said packer means having a plurality of circumferentially spaced apertures for relief of any back pressure provided by the increased hydraulic fluid pressure, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

7. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictionally engaging the wash-over pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, a bushing connected to the lower end of the mandrel for a make up connection with the stuck fish, means on the bushing adapted to receive a Wrench prior to disposition of the retrieving tool in the well bore to provide rotation thereof simultaneous with the mandrel to cause vertical movement of the wedge 1n the direction to cause engagement of the slips with the wash-over pipe, said cooperating means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotatlon to move the wedge in a direction opposite first mentioned direction, means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, means cooperating between the sleeve and the slips to move the slips radially inward in the last mentioned position of the wedge, means providing for fluid circulation through the retrieving tool, and flexible packer means carried by the slidable sleeve and responsive to an increased hydraulic pressure of the fluid circulation to maintain the sleeve in a position to preclude engagement of the slips upon any vertical upward movement of the wash-over pipe, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement Iciafhthe slips with the wash-over pipe to catch the loosened 8. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the wash-over pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternatelv operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, a bushing connected to the lower end of the mandrel for a make up connection with the stuck fish, means on the bushing adapted to receive a Wrench prior to disposition of the retrieving tool in the well bore to provide rotation thereof simultaneous with the mandrel to cause vertical movement of the wedge in the direction to cause engagement of the slips With the wash-over pipe, said cooperating means between the mandrel and the wedge responsive to an up ward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the mandrel and the wedge to provide an interlocking therebetween in the last mentioned position to permit said slips to move away from the wedge to a released position in response to downward movement of the wash-over pipe, means providing for fluid circulation through the retrieving tool, and spaced flexible packer means carried by the slidable sleeve, the uppermost of said packer means responsive to an increased hydraulic pressure of the fluid circulation to maintain the sleeve in a position to preclude engagement of the slips upon any vertical upward movement of the wash-over pipe, the lowermost of said packer means having a plurality of circumferentially spaced apertures for relief of any back pressure provided by the increased hydraulic fluid pressure, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

9. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the Wash-over pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the washover pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips,

means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said cooperating means between the mandrel and the wedge responsive to an upward pull of the washover pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the sleeve and the slips to move the slips radially inward out of engagement with the wash-over pipe in the last mentioned position of the wedge, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

10. In a wash-over apparatus for retrieving a stuck fish in a well bore comprising a wash-over pipe having a retrieving tool adapted to be positioned therein, said tool comprising an elongated mandrel, a sectional sleeve slidably disposed on the mandrel, friction dog means carried by the sleeve for frictional engagement with the washover pipe, a plurality of circumferentially spaced slips carried by the sleeve and alternately operable for a gripping and non-gripping engagement with the wash-over pipe, upwardly and outwardly tapered wedge means carried by the mandrel and engageable with the slips, left hand thread means cooperating between the mandrel and the wedge means and responsive to rotation of the mandrel in one direction prior to disposition of the retrieving tool in the well bore to move the wedge means in a direction to provide for radial outward movement of the slips for engagement with the wash-over pipe, means connected to the mandrel for a make up connection with the stuck fish, said left hand thread means between the mandrel and the wedge responsive to an upward pull of the wash-over pipe and slips with a simultaneous rotation thereof in a direction opposite to that of the first mentioned rotation to move the wedge in a direction opposite to that of the first mentioned direction, means cooperating between the sleeve and the slips for moving the slips radially inward to a released position in the last mentioned position of the wedge, a J-shaped recess provided in the mandrel, and an aperture provided in the sleeve adjacent the recess and adapted to receive a key extending therethrough into the recess for locking the mandrel and sleeve in one position of the wedge to maintain the released position of the slips, said wedge responsive to a downward movement of the mandrel upon loosening of the stuck fish to provide for an engagement of the slips with the wash-over pipe to catch the loosened fish.

References Cited in the file of this patent UNITED STATES PATENTS 2,762,438 Naylor Sept. 11, 1956 

